Failure Mode Analysis of 11 kV Outdoor Polymeric Insulators

Silicone Rubber (SiR) insulators are known for their outstanding pollution performance in outdoor applications. However, their vulnerability for multiple stresses and many failure modes limits their applications in the power sector. A study is conducted to analyze the cause of their failure in service. Most of the failures occurred due to tracking in the core material, erosion of housing and damages caused by the discharges to the end fittings. It is realized that most of the failures occur due to inefficient manufacturing processes and lack of knowledge which lead to premature failures of the insulators and underutilization. Addressing these issues are need of the hour to increase the applications of polymeric insulators.